... famous gangster first (1-4)
I believe the answer is:
a-list
'famous' is the definition.
(I've seen this before)
'gangster first' is the wordplay.
'gangster' becomes 'al' (Al Capone).
'first' becomes 'ist' (ist resembles 1st).
'al'+'ist'='A-LIST'
(Other definitions for a-list that I've seen before include "Most celebrated people" , "Very famous" , "of the best sort" , "Acclaimed" , "Top celebrity group" .)